Abstract

A non-linear model is introduced describing the force-deflection relation of doubly clamped beams, including initial stress. Several approximations for the exact model are developed and compared, revealing the importance of considering the initial stress during 3-point bending measurements analysis. A novel approximation is found to be better than others, and both the exact model and this approximation are in perfect agreement with finite element simulations. A brief experimental example of siliconnanowires is presented in which the Young's modulus, the initial stress, and the crystallographic growth orientation are extracted by 3-point bending analysis.

The authors thank the Russell Berrie Nanotechnology Institute, the Micro Nano Fabrication Unit at the Technion, and the Israeli Ministry of Industry, Trade and Labor via the MAGNET program (ALPHA Consortium) for their support.